It was a "political attack of the kind that shows how debates about human rights are curtailed by powerful conservative political forces in Russia", said Fare director Piara Powar in a statement on Saturday.

He pointed to a long history of rights groups being closed or pressured on legalistic pretexts in Russia, and particularly in St Petersburg.

New premises in the city centre have since been found and opened on Saturday, organisers said.

Homosexuality was decriminalised in Russia in 1993, but anti-gay prejudice is rife.

Five years ago, the Russian Duma passed a law that made "propaganda of non-traditional sexual relationships" among minors an offence.

Football's ruling body Fifa, which works with Fare, said it had contacted St Petersburg authorities to try to find a solution and said it "regretted" what had happened.

Another Diversity House in Moscow is open and has been running events.